If the fictional Santa Monica doctor from the early 1970s were still plying his trade today, patients would be able to find him at the touch of a smartphone application. He would listen to their woes and conduct a quick triage over the phone, deciding whether the symptoms warranted a house call, an ER visit or nothing at all.

Medicast, a startup that launched in Miami last summer, offers exactly such an app — and a network of doctors to go with it. The company, which has big plans for nationwide expansion, just opened shop in Los Angeles earlier this month.

And that's not TV fiction.

It is part of a growing trend in on-demand consumer services, notably exemplified by Uber, the mobile-driven taxi request service that has provoked the ire of taxi drivers around the globe.

It is also the latest frontier in the burgeoning world of telemedicine — a world in which medical test results can be transmitted over smartphones in a heartbeat and companies such as Teladoc, MDLive and American Well connect patients with doctors in videoconferences or over the Internet.

Unlike those companies, whose bread and butter is virtual consultation, Medicast collects only if the doctor makes a house call in the flesh. No visit, no charge.

In a nod to the calmer, kinder era of house-calling physicians it evokes, Medicast also makes its service available on the company's website. It even has an old-fashioned 800 number for the Luddites among us.

"We want to make it available to anyone, which is why we have all three options," said Sam Zebarjadi, Medicast's CEO and co-founder.

At the same time, Zebarjadi said, Medicast "is focused on the 30- to 64-year-old market — people with an affinity for technology and some interest in fitness and wellness."

The company has only five full-time employees — Zebarjadi, two other co-founders and two marketing people. Medicast contracts with its doctors — 20 in Los Angeles and five in Miami so far, though Zebarjadi envisions the network growing to hundreds of physicians.

The company charges $249 for a home visit, and the doctor keeps $170 of it. In addition to the patient-doctor introductions, Medicast provides billing and other back-office services. Monthly plans are available: $39 a month entitles you to two visits a year; for $75 you get four.

Medicast's service is not generally covered by health insurance, but prescription drugs might be covered, and some insurers will count the cost of the house calls against a patient's deductible for out-of-network services.

People in need of medical services can consult the profiles of on-call Medicast doctors — as well as reviews from previous patients. If they decide to request a consultation, they are asked to enter their credit card information. They will get a call from one of the doctors within a couple of minutes. If the doctor decides a house call is in order, the credit card will be charged.

What Medicast offers is a form of "concierge" medicine, in which patients agree to pay out of their own pockets for quicker access and longer visits with doctors. Zebarjadi thinks the company stands to profit from the fact that many primary-care doctors are overburdened.

"With urgent-care centers crowding up and retail clinics packed to the rafters, we see big opportunity," he said.

And with annual deductibles on health plans rising as high as $5,000, "a lot of people are starting to forgo their insurance and going to a service like ours. Because they're going to pay the same out of pocket. So why pay for subpar service?"